Master of Science in Ecological Restoration Applied Research Projects | BCIT Institutional Repository

Master of Science in Ecological Restoration Applied Research Projects

Alaksen National Wildlife Area: Reservoir suitability for the introduction of the endangered Western Painted Turtle
Alaksen National Wildlife Area located in Delta, BC is home to freshwater species in the former tidal marsh. The current agricultural landscape has left a legacy of high concentrations of heavy metals, trace amounts of organochlorine pesticides, and excess nutrients within the sediments and water of the brackish Fuller and Ewen Reservoirs. Arsenic and phosphorous exceeded Canadian water quality guidelines, while arsenic, chromium, copper, iron, manganese, nickel, and phosphorus exceeded sediment quality guidelines. There were trace pesticides known to be endocrine disrupters detected in the water and sediment, and combined low level toxicity effects are a concern. A preliminary ecological risk assessment on the metals was completed and the results indicate that there is a possibility of adverse effects for benthic invertebrates, but negligible risk for endangered Western Painted Turtles. However, compounding all the ecosystem stressors along with rising sea levels leads ANWA not an ideal place to introduce this species., © Darian Weber, 2019. All rights reserved. No part of this work covered by the copyright heron may be reproduced or used in any form or by any means – graphics, electronic, or mechanical including photocopying, taping, or information storage and retrieval systems – without written permission of the author., Western Painted turtles, ecotoxicology, risk assessment, agricultural reservoir, heavy metal, endocrine disruptors
Assessing the allelopathic effect of invasive phragmites australis on sida hermaphrodita and ammannia robusta; two species at risk in Southern Ontario
In Ontario, invasive Phragmites australis threatens to displace many species including the endangered species Sida hermaphrodita and Ammannia robusta. Germination and growth assays measured the effect of P. australis aqueous extracts from the leaves, rhizomes, and roots on S. hermaphrodita and A. robusta. Germination was inhibited by some of the treatments, but growth was not. The tissues inhibited germination differently for S. hermaphrodita (leaf> rhizome> root) compared to A. robusta (root> rhizome> leaf) indicating that the allelopathic effect was species-specific. However, the laboratory results show that allelopathic effects are weak. This result is consistent to the field study results showing an increase in S. hermaphrodita area and density over time. Results from this project inform management options by indicating which part of the plant needs to be targeted. In this case, all the tissues had some phytotoxic effects, indicating that biomass may need to be removed or long-term management implemented., Invasive Species, Species at Risk, Seed Germination, Seedling Growth, Allelopathy
Ecocultural restoration of a Coastal Root Garden on Tl’chés (Chatham Island), B.C.
Tl’chés is the Lekwungen name for the Chatham Islands — an archipelago located southeast of Victoria, British Columbia. Tl’chés is a central place in the traditional territory of the Lekwungen peoples, and today it is reserve land of the Songhees First Nation. This landscape was traditionally managed by prescribed burning and the cultivation of native plants. However, in the early 1950's, Lekwungen peoples left the archipelago, due to a lack of potable water and since then, the landscape has degraded drastically. The introduction of non-native plants has resulted in threats to the ecological, cultural resilience, and diversity of the landscape. My research focuses on developing a restoration plan for springbank clover in the coastal root garden. My restoration approach focuses on incorporating a Songhees-informed approach to restoration by integrating past practices and knowledge with the aim of answering: how to best restore the springbank clover population on Tl’chés?, Eco-cultural restoration, coastal root gardens, traditional ecological knowledge (TEK), Songhees First Nation, cultural keystone place (CPK)
An ecological restoration plan for a weedy field at the University of British Columbia Okanagan
Grassland ecosystems are rare, in decline, and support a multitude of at-risk species in British Columbia. At the University of British Columbia Okanagan in Kelowna BC, a 3.3 ha site at the entrance of the campus is outlined as Okanagan grassland in campus design plans but currently lacks native bunchgrass communities. The goal of this restoration plan is to return grassland plant communities to the site despite the pervasiveness of noxious weeds. I characterised site conditions through soil and vegetation surveys. Restoration recommendations include managing noxious weeds through mowing, hand-pulling and some herbicide application. The site will be replanted with bunchgrass vegetation, two pockets of ponderosa forest, and two types of shrub communities. A walking path, signage, and two xeriscape gardens will also be included to control human use of the landscape. Long-term monitoring will be incorporated into classroom curricula to tie monitoring to learning opportunities., Grassland, exotic plants, Noxious weeds, urban restoration, restoration plan
The effects of tree thinning and broadcast burning on the quality of ungulate winter range: a case study within a Southern Interior Forest in British Columbia
Food limitation on ungulate winter range (UWR) has been a suspected factor in the regional declines of Odocoileus hemionus (mule deer) in the Pacific Northwest. Accordingly, enhancing browse resources in this critical habitat is increasingly recommended. At a dry forest site in Southeast B.C. called Fiva Creek (IDF dm1), I investigated the effects of two commonly prescribed methods for enhancing browse production: tree thinning and prescribed burning. Treatments were implemented between 2005–2008 and included three levels of thinning (all burned) and control areas (uncut and unburned). The response variables I measured included browse cover, canopy closure, security cover, visibility, and pellet abundance. I also evaluated browsing pressure on the indicator plant, Saskatoon (Amelanchier alnifolia). Using linear mixed-effects ANOVA tests, I assessed how thinning (with follow-up burning) influenced forest and vegetation properties. There was no evidence of a treatment effect on browse production; however, browsing pressure was very high across the site (i.e., > 80% of A. alnifolia twigs showed evidence of browsing). Additionally, canopy cover was below recommended levels in all thinned treatments. My results suggested that restoration treatments actually diminished the quality of UWR at Fiva Creek. Further investigations are needed to develop effective UWR restoration methods., Mule deer, ungulate winter range, thinning, prescribed fire, restoration ecology
Identifying temporal trends and mechanisms for successful reforestation on former agricultural land
This study investigates the outcomes of restoration efforts completed on retired agricultural land in Southwest Ontario. Sites acquired by the Nature Conservancy of Canada were planted to kickstart succession to native deciduous forests, but the results of the plantings are mixed. Analysis of soil conditions indicated that low levels of soil organic carbon were correlated to low water content and high density unfavourable for plant growth. Analysis of remotely sensed imagery was done to assess and compare vegetation cover to reference conditions at Walpole Island First Nation. Analysis revealed that successful restoration was dependent on multiple soil characteristics, but conditions correlated to higher total organic carbon favoured greater vegetation cover. Remote sensing data revealed that succession towards tree canopy development was accelerated compared to passive restoration, and a shaded understory was established approximately 8-12 years following restoration. Future work can expand on succession and the effects of other restoration treatments., Soil, Reforestation, NDVI, Agriculture, Restoration, Secondary succession
Investigating regeneration in a raised ombrotrophic bog after peat extraction
Burns Bog is a raised ombrotrophic bog in Delta, British Columbia and faced with myriad disturbances. This study is focused on the impact and restoration of peat extraction by the Atkins-Durbrow Hydropeat method. Depth to water table, relative abundance and distribution of vegetation, and the degree of peat decomposition at consistent-depth intervals were investigated to elucidate the status of passive and active ecological restoration in three fields previously harvested for peat approximately one decade apart and compared to a fourth unharvested field. Summary statistics, Redundancy Analysis, and regression were used to compare restoration status and trends in hydrology, vegetation composition, and peat accumulation. A lag period between cessation of harvest and implementation of restoration, coupled with rapid anthropogenic climate change, serve as impediments to restoration here. Intervention in the form of improved rainfall retention, assisted recolonization, and the introduction of nurse species are recommended to improve bog function and resiliency., Atkins-Durbrow Hydropeat method, Ditch blocking, Ecological restoration, Peat extraction, Raised ombrotrophic bog, Burns Bog
Mapping floodplain fish habitat in the heart of the Fraser River and restoration options for impacted attributes on selected large mid-channel islands
The purpose of this project is to develop an ecological restoration plan for degraded habitats on mid-channel islands in the lower Fraser River. The study focuses on Herrling, Carey, and Strawberry islands, large mid-channel islands located in the gravel reach between Mission and Hope, British Columbia. These islands are known to be critical off-channel rearing habitat for many fish species including the threatened White Sturgeon (Acipenser transmontanus) and interior and lower Fraser watershed Chinook Salmon (Oncorhynchus tshawytscha) populations. These islands are also home to many riparian plant and animal species. The flood-pulse concept (FPC) states that seasonal fluctuations in water levels for streams such as the Fraser River contribute substantially to the ecological function of the floodplain ecosystem where this phenomenon occurs. This often results in improved growth and survival rates for fish species that rely on a laterally-moving littoral zone of inundation. This phenomenon is thought by many to be the key to a properly functioning ecosystem in the lower Fraser River. Using a Digital Elevation Model (DEM) for the Fraser River between Hope and Mission, British Columbia, freshet flows (high water elevations) are presented to define the spatial extent of over-bank watering of Strawberry, Carey and Herrling islands. This over-bank watering provides lateral connectivity to floodplain islands. Based on extensive sampling in other studies, this lateral movement results in the creation of high-quality juvenile fish rearing habitat. A restoration plan is presented for those areas of Strawberry, Carey and Herrling islands degraded by recent land clearing for agriculture where they overlap sections defined as fish habitat from the spatial analysis., gravel reach, mid-channel islands, floodplain fish habitat, flood pulse concept, juvenile Chinook Salmon, lower Fraser River, White Sturgeon
Plant facilitation effects as a potential restoration tool in riparian ecosystems in Southwestern British Columbia
This study began to investigate potential facilitative effects among shrub species in riparian ecosystems in southwestern British Columbia. I ran two concurrent studies. Six plots for each of four treatments were established at the Coquitlam River Wildlife Management Area. The first two treatments compared the survival, growth, flowering, and herbivory rates of planted twinberry seedlings in plots where the shrub layer was removed to plots where it was not. The other two treatments compared the survival, growth, leaf loss, flowering and herbivory rates of snowberry plants in plots where the salmonberry upper shrub layer was removed to those where it was not. No significant differences between the measured parameters in any of the treatments were found. These results are discussed in the context of the riparian forest ecosystem and current facilitation theory. The results are then used to inform an ecological restoration plan for the Suwa’lkh School Forest., Facilitation, Riparian forests, Native vegetation, Symphoricarpos albus, Lonicera involucrate, Rubus spectabilis, Ecological restoration
Restoring a culturally eutrophic shallow lake: Case study on Quamichan Lake in North Cowichan, British Columbia
Quamichan Lake is a culturally eutrophic shallow lake located in North Cowichan on Vancouver Island in British Columbia. My research project examined the current trophic status and water quality of Quamichan Lake and investigated a number of watershed and in-lake restoration methods to return the lake back to mesotrophic (nutrient rich) conditions. Based on the data collected, Quamichan Lake is currently in a hypertrophic state caused by excess phosphorus inputs that leads to Cyanophyte phytoplankton species (cyanobacteria) to dominate during the summer. Eutrophication is both an environmental and human health issue as cyanobacteria algal blooms can disrupt the lake ecology and are toxic to most mammals. The goal of my research was to provide the Municipality of North Cowichan and Vancouver Island Health Authority with a comprehensive restoration plan to contribute to the restoration of Quamichan Lake and other lakes in southern Vancouver Island that are experiencing cultural eutrophication., © Kathleen E Moore, 2019. All rights reserved. No part of this work covered by the copyright heron may be reproduced or used in any form or by any means – graphics, electronic, or mechanical including photocopying, taping, or information storage and retrieval systems – without written permission of the author., Eutrophication, Limnology, Watershed Management, Cyanobacteria, Restoration
Restoring hydro-impacted wetlands for secretive marsh birds
Secretive marsh birds can be difficult to detect and are dependent on wetlands, leaving them vulnerable to wetland loss or alteration. This study examines the influence of management-altered hydrological regimes on five secretive marsh bird species in the West Kootenay and Columbia Wetlands in British Columbia, Canada. Focal species occupied wetlands with less frequently altered hydrological regimes more often and in greater numbers. Occupancy models suggested that woody vegetation, tall vegetation, and open water are important drivers of occupancy for these species. Wetlands most frequently experiencing heavily altered hydrological regimes had more open water and less tall vegetation, both of which were negatively associated with wetland occupancy. Water management operations may be promoting altered vegetation communities within these wetlands, in turn promoting lower occupancy of secretive marsh bird species. Restoration recommendations include: prioritizing lower elevation wetlands, limiting woody vegetation encroachment, and experimentally restoring the hydrological regime of affected wetlands., © Ashleigh M. Westphal 2019. All rights reserved. No part of this work covered by the copyright heron may be reproduced or used in any form or by any means – graphics, electronic, or mechanical including photocopying, taping, or information storage and retrieval systems – without written permission of the author., secretive marsh bird, Kootenays, British Columbia, hydro, water management, wetlands
Splendor without spoil: restoring tidal channel habitat on Swishwash Island
Restoration of estuarine and tidal marsh habitats in Canada’s Fraser River estuary is imperative for the conservation and recovery of select depressed Pacific salmon populations and the many species that depend on them. In the 1930’s through to 1940’s, dredge spoils were deposited on East Swishwash Island, permanently altering the small delta island’s geomorphology and ecology. The purpose of this study was two-fold: 1.) Confirm and describe fish use of remnant tidal channel habitat on Swishwash Island, using juvenile Chinook salmon (Oncorhynchus tshawytscha) as a focal species and 2.) Quantify the historical tidal channel loss on East Swishwash Island and potential for restoration. Tidal channels and adjacent marshes were sampled for realized fish use, plant distributions, basic water parameters, and large woody debris (potential predator refugia). Remote data sets (historical and present-day) were used to quantify historic, current, and future tidal channel density scenarios. Swishwash tidal channels were utilized during the sampling period by Chinook salmon with comparable relative abundances and fork lengths. Tidal channel capacity and marsh habitat have been reduced by 50% on East Swishwash Island due to spoil deposition and marsh erosion. Based on reference conditions derived from undisturbed and historic marsh islands, restoring island elevations could facilitate the addition of 1 km of marsh edge while increasing tidal channel area on East Swishwash Island by nearly 200%. This would provide important habitat in a fragmented distributary of the Fraser River estuary to species of fish and wildlife, including 3 ecotypes of juvenile Chinook salmon., © Kyle Armstrong, 2019. All rights reserved. No part of this work covered by the copyright heron may be reproduced or used in any form or by any means – graphics, electronic, or mechanical including photocopying, taping, or information storage and retrieval systems – without written permission of the author., Estuaries, Chinook, Oncorhynchus tshawytscha, rearing, restoration, mitigation, tidal channels